title: Pilot study assessing the effectiveness of long-lasting permethrin-impregnated clothing for the prevention of tick bites.
abstract: BACKGROUND
  Tick-borne diseases such as Lyme disease, Rocky Mountain spotted fever, and ehrlichiosis are a significant concern for many thousands of workers who have frequent and unavoidable exposure to tick-infested habitats. Many North Carolina state employees with outdoor occupations report multiple tick bites each year, indicating that existing tick preventive strategies may be underutilized or ineffective. Treatment of clothing with permethrin, a nontoxic chemical with insecticidal, knockdown, and repellent properties, is highly effective against ticks. However, most permethrin products must be reapplied after several washings to maintain insecticidal activity. Recently, a factory-based method for long-lasting permethrin impregnation of clothing has been developed by Insect Shield, Inc., that allows clothing to retain insecticidal activity for over 70 washes.
  
  
  METHODS
  A nonrandomized open label pilot study was conducted to determine the effectiveness of Insect Shield-treated clothing for the prevention of tick bites among 16 outdoor workers from the North Carolina Division of Water Quality under actual field conditions. Participants completed questionnaires at the start of follow-up (March, 2008) and at the end of follow-up (September, 2008), and tick bites and outdoor work hours were reported on weekly tick bite logs for the entire follow-up period.
  
  
  RESULTS
  Subjects wearing Insect Shield-treated clothing had a 93% reduction (p < 0.0001) in the total incidence of tick bites compared to subjects using standard tick bite prevention measures.
  
  
  CONCLUSIONS
  This study provides preliminary evidence that long-lasting permethrin-impregnated clothing may be highly effective against tick bites.
authors.affiliation: Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, North Carolina 27599-7435, USA. meagan.vaughn@unc.edu
authors.forename: Meagan F
authors.initials: MF
authors.lastname: Vaughn
authors.forename: Steven R
authors.initials: SR
authors.lastname: Meshnick
mesh_terms: D000328:Adult; D000818:Animals; D001733:Bites and Stings / Q000453:epidemiology / Q000517:prevention & control*; D003020:Clothing; D005260:Female; D006801:Humans; D007306:Insecticides / Q000008:administration & dosage*; D008297:Male; D008875:Middle Aged; D009657:North Carolina / Q000453:epidemiology; D016273:Occupational Exposure / Q000517:prevention & control*; D026023:Permethrin / Q000008:administration & dosage*; D010865:Pilot Projects; D012044:Regression Analysis; D011795:Surveys and Questionnaires; D013987:Ticks
chemical_list: D007306:Insecticides; D026023:Permethrin